Emotional tears are thought to be uniquely human and have puzzled biologists and psychologists for many years. Using a double-blind study comparing female emotional tears with control saline, Gelstein et al. investigated whether human tears may convey a chemosignal. Even though the tears could not be smelled, tears nevertheless decreased the sexual appeal of women’s faces. Female tears also lowered sexual arousal and reduced testosterone levels in men. A subsequent brain imaging study highlighted differences in functional activation in the brain. Emotional tears thus seem to contain chemosensory signals related to sociosexual behavior.